Modern vehicle design involves configuration of various sensors and actuators spread across the vehicle. These sensors and actuators placed at various locations in the vehicle need to be connected with Electronic Control Units (ECUs). As long as wires are used for these connections, cost and time required for installation and maintenance are major concerns for OEMs. A wireless sensor network (WSN) can reduce length of wiring harness and can save time as well as cost of its installation. It also provides flexibility in deciding location of ECU according to desired shape of the vehicle. This paper presents a way to build a strong, secured wireless network in vehicle. The proposed method of encryption and decryption ensures that, sensor and actuator data is available only to required ECUs and not to any other unintended receiver. A novel method is proposed in order to achieve this. Sensors and actuators in the vehicle are segregated according to their location. Hence, single wireless node can be used to get data from sensors as well as to control actuators located at a particular region. E.g. Rear ultrasonic parking sensors and rear light console can be connected to their respective ECUs via single wireless node in ‘rear zone’. Further, use of directional antenna instead of traditional Omni-directional antenna reduces power consumption and interference of signals.